This invention relates to a reaction vessel or tank structure for use in a suspension polymerization for the manufacture of polyvinyl chloride or vinyl chloride.
In the polymerization process there is an excessive heat build up due to the reaction process and it is necessary to remove such heat to control the speed of reaction process. As larger apparatus or vessels are used to more economically provide the end product it has become necessary to use thicker walls to provide the necessary strength to withstand the increase in pressure. However with this increase in size of vessel and wall thickness there is also a substantial increase in the need to more efficiently remove the heat to properly control the reaction process.
The prior art provision of removing heat in the form of cooling tubes within the reactor vessel is unsatisfactory because of the difficulty of cleaning the interior walls of the vessel and the exterior walls of the cooling tubes due to polymer adhesion thereto and the resulting build-up or accumulation thereon. The provision of external cooling jacket encompassing the reactor vessel has presented the problem of not providing sufficient cooling capacity because of the thickness of the vessel wall prevents efficient cooling. The instant invention provides an internal cooling jacket with a thin innermost wall as one continuous surface thereby presenting a smooth inner wall which inhibits the unsatisfactory build-up of polymer adhesion and accumulation.